The present disclosure relates to a vibration power generator, a vibration monitoring device, and a vibration monitoring system.
A piezoelectric element is an element which induces electric polarization and generates a voltage when a pressure in a specific direction is applied thereto. By utilizing such a piezoelectric element, mechanical displacement is converted into voltage, and power can be thus generated. Common mechanical displacements include vibration. If power can be generated by vibration, electronic devices will be able to be operated almost anywhere without preparing a power supply.
Methods for generating power by vibration include a method using a vibrating piezoelectric material including a piezoelectric element attached to a diaphragm. Unfortunately, in this method, if the resonant frequency of the vibrating piezoelectric material is identical to the frequency of vibration, a large mechanical displacement is obtained, and power can be thus generated, whereas if the resonant frequency differs from the frequency of vibration, power can hardly be generated. For this reason, consideration has been made to extend the range of vibration frequencies within which power can be generated using a plurality of vibrating piezoelectric materials having different resonant frequencies (see, for example, Japanese Unexamined Patent Publication No. 2011-152004).